Fuel cells have recently been highlighted as cells that exhibit a high level of efficiency and excellent environmental characteristics. In a fuel cell, generally, the oxygen within air, which functions as an oxidant gas, is subjected to an electrochemical reaction with hydrogen, which functions as a fuel gas, thereby generating electrical energy. As a result of the electrochemical reaction between the hydrogen and oxygen, water is generated.
Varieties of fuel cell include phosphoric acid fuel cells, molten carbonate fuel cells, solid electrolyte fuel cells, alkali fuel cells and solid polymer fuel cells. Of these, solid polymer fuel cells, which offer certain advantages such as ambient temperature startup and a rapid startup time, are attracting particular attention. This type of solid polymer fuel cell can be used as the power source for moving objects such as vehicles.
A solid polymer fuel cell is assembled by laminating a plurality of unit cells, a current collector and an end plate and the like. Each unit cell for the fuel cell comprises an electrolyte membrane, catalyst layers, gas diffusion layers and separators.
Patent Document 1 discloses a fuel cell having a structure in which a gas diffusion layer comprising a fibrous material is sandwiched between an electrode and a metal separator, wherein a layer of a corrosion-resistant conductive material such as gold (Au) or the like is formed by vapor deposition, sputtering or plating or the like on the gas diffusion layer side of the structure, without forming a plating layer of a corrosion-resistant conductive material such as gold (Au) or the like on the metal separator side of the structure.
Patent Literature 1: JP 2004-178893 A